Chill mold



Feb. 14, 1928. 1,658,835

F. C. T. DANIELS ET AL CHILL MOLD Original Filed y 1925 l4 INVENTORIfrzd- ZYZTDW m6 ATTOVRNEYS QIIGB'W Patented Feb. 14, 1928.

UNITED STATES ram 0. T. nanmns PATENT OFFICE.

AND WILLIAM H. MoCAUSLAND, or BETHLEI IEM, rnnnsynvnnra, Assfenons ToBETBLEHEM srnnn CO PANY."

CHILL MOLD.

Application filed. May 20, 1925, Serial .No. 31,517., Renewed August 1,1927.

' Our invention relates'to chillmolds and particularly to that type ofmold sect on used in the casting of rolls. Heretofore ch ll molds havebeensuggested in wh ch the chilling surface, which is in contact w ththe articles cast thereimisformed of a plurality of'segments separatedby slots which allow forthe uniform expansion and contract on ofthe noldduring the casting operation. The practicehas been to fill such slotswith refractory material so as to present a smooth interior face tominimize the formation of fine ,on the surface of ,the casting.

The refractory material 's easily dislodged and must be frequentlyreplaced. Furthermore, the metalat the surface of the article cast inmold opposite the slots solidifiesdifferent-ly from the surface indirectcontact with theiiietal of the iniolcl and results in longitudinallyextending portions of the metal which have a different form of crys-.

tallization than the remaining metal; and, as such portions usuallyextend in straight lines, the abrupt change in the crystalline structureat'this portion causes initial strains at the surface ofthe' articlecast with the development of splits and cracks when such articles are inservice. This is particularly so in the case of rolls used in the hotrolling of sheets and the like where the rolls are subjected to severestresses at the surface due to the expansion and contraction of the rollin a well known manner.

Our invention, therefore, has for its .object to provide chill sectionsfor molds for casting rolls and the like which sections are .providedwith sinusoidal or curvedslots in order to hold refractory material tobetter advantage and in order to so dispose the crystalline structure ofa casting that.the danger of cracks when the latter is placed in servicemay be minimized.

The preferred embodimentof the inven tion is illustrated in theaccompanying drawing wherein- Fig. 1 is 'a plan view of the moldsection;

Fig. 2 is a cross sectional view taken on line II-II of Fig. 1;

Fig. 3 is apartial cross section taken on line III-III of Fig. 2somewhat enlarged and, i

Fig. lis a view of the chilling face of the mold section showing amodification.

Referring to the drawings, 10 designates and contraction due totemperaturechanges;

The segments are separated from each other by theradial slots 13 and areconnectedto the annular portion '14 of the mold section.

,Theslots extend into cored openings which allow the escape of the gasesevolved during the casting of the articles in the mold. The slots 13 arewaved in the general longitudinal direction, as shown in Fig; .2, andeach preferably hascurved portions-extending to both sides of av plane,indicated by the line 16, through the axis of the mold.

A filler 17 is inserted in each of the slots 13 so that the face of themold in contact ,with the .articlerast is a smooth continuous surface,thereby preventing the formation of fins on the face of said article.Waving of the slots assists in retaining the fillers 17 in place. Notonly are the fillers firmly supported due to the curved formation, butmovement thereof is resisted even though the chill section may expand;

The fillers are preferably of asbestos or similar material which isrefractory and permeable to gases. Asbestos may be prepared in stripform, and such strips are bent to the required waved formation andplaced in position in the flask in which the mold section is cast, andconstitute the core members for forming the slots 13. The asbestosstrips remain in the slots after the mold section is removed from theflask and constitute the fillers 17. I

p A further novel feature of our invention is the configuration of theslots with relation to the soft spots usually formed on the surcast indirect contact with the metal of the mold, which results in there beingformed in the cast rolls longitudinally extending portions of metalwhich have a different form of crystallization from the remaining metal.This results in'a difference in the stiffness of the material of rolls;and, if

used for rollingsheets, thelatter are marked in a curved manner, andsuch curved markings are more easily removed in the subsequent rollingin the finishing mill than is the case with straight markings.

A further advantage of the curved formation of slots resides in the factthat, the material of rolls cast will be disposed to better advantage toresist the formation of cracks in service for the reason that the lineof pressure or a roll will never coincide with a longitudinallyextending weakened portion'but'will always cross the softer portions. Inother words, a roll so formed has a better average'strength." hile weprefer to have the slots 13 extending insinuou-s curves, it will beobvious that such slots may extend assingle curves .from edge toedge ofa section, for slots 13 of the latter character are shown 'in Fig. 4:.

example,

While"we haveshown our invention in two forms, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifications without departing from thespirit thereof, and we desire, therefore, that only such limitationsshall be placed thereupon'as are imposed by the prior art or as arespecifically set forth in the appended claims. I

We claim: I V 1. A mold having an inner chill portion divided by sinuouscurves'iuto a plurality of sections. i

2. An integral mold having an inner chill portion divided by sinuouscurves into a plurality of longitudinal sections, the slits between suchsect-ions containing a tiller.

3. A one-piece, annular sectional chill mold having an annular series ofcast openings extending in an axial direction with respectto the moldand cast slots extending inwardly from the openings for dividing theinner or chill portion of the mold into an. annular series of separatedsegments, said slotsextending insinuous curves in an axial direction. If

14. A one-piece, annular sectional chill mold having an annular seriesof'radiallydisposed oblong cast openings extending axially with respectto the mold and cast slots extending inwardly from the inner ends of theopenings for dividing the inner or chill portion of the mold into anannular series of separated segments, said slots extending in sinuouscurves in 'an' axial direction.

In testimony whereof I hereunto afiix my signature this lath day of May,1925.

v FRED G. T. DANIELS. In testimony whereof I hereunto aflix my signaturethis 14th day of May, 1925.

WILLIAM H. MGCAUSLAND.

